Plastic raft

ABSTRACT

A LIGHTWEIGHT PLASTIC RAFT INCLUDING A TOP SUPPORT SURFACE WITH A DEPENDENT RIGID FOAM PLASTIC RING SIDE PROVIDING FLOTATION AND DEFINNINF A CENTRAL AIR CHAMBER. SLIGHTLY SPACED, SEGMENT SHAPED, RIGID CORES ARE PROVIDED FOR THE TOP JOINED BY THE FIBRE GLASS RESIN COMPOSITION WITH WHICH THE TOP IS COATED. A VALVE COMMUNICATE THE AIR CHAMBER WITH ATMOSPHERE AND PERMITS RAFT TO BE VACUUM LOCKED TO THE WATER.

2 Sheets-Shoot 1 PLASTIC RAFT E. J. KELLER Nov. 16, 1971 Filed May 13,1969 Nov. 16, 1971 E. J. KELLER 3,619,833

PLASTIC RAFT Filed May 13, 1969 2 Sheets-Shoot B HTTORNEYS United StatesPatent Office 3,619,833 Patented Nov. 16, 1971 3,619,833 PLASTIC RAFTErvin J. Keller, G-4382 Lippincott, Flint, Mich. 48507 Filed May 13,1969, Ser. No. 824,101 Int. Cl. B63c 9/ 04 U.S. Cl. 9-11 8 ClaimsABSTRACT OF THE DISCLOSURE A lightweight plastic raft including a topsupport surface with a dependent rigid foam plastic ring side providmgflotation and defining a central air chamber. Slightly spaced, segmentshaped, rigid cores are provided for the top joined by the fibre glassresin composition with which the top is coated. A valve communicates theair chamber with atmosphere and permits the raft to be vacuum locked tothe water.

One of the prime objects of the invention is to provide a lightweightraft of attractive and pleasing appearance which is relativelyeconomical to fabricate and requires no malntamence.

Another object of the invention is to provide a strong and durable raftof the character described which can be readily installed and removedfrom installed position.

A further object of the invention is to provide a raft of the characterdescribed which may be locked in a position of adjusted height in thewater and at the same time locked in a stabilized position whichprevents tipping.

Still another object of the invention is to design a selfdraining rafthaving an upper surface configured so that it is comfortable for sunbathing but at the same time provides a non-slip surface when wet.

Another object of the invention is to provide a raft which avoids anyproblems with bathing suits snagging or slivers.

Other objects and advantages of the invention will become readilyapparent when considered with the attached description and with theaccompanying drawings.

Briefly, in its broad aspect the invention is concerned with a fibreglass raft including segmented cores and having a wall side formed `by aotation providing member.

In the drawings:

FIG. 1 is a perspective plan view of my raft;

FIG. 2 is a top plan view thereof;

FIG. 3 is a partly sectional, side elevational View;

FIG. 4 is an under plan view with a portion partially broken away toexpose the interior construction thereof;

FIG. 5 is a considerably enlarged, fragmentary, sectional elevationalview taken on the line 5 5 of FIG. 2;

FIG. 6 is a fragmentary, enlarged plan view illustrating theconfiguration of the tread surface; and

FIG. 7 is a sectional elevational view thereof.

Referring now more particularly to the accompanying drawings, a letter10 generally designates a raft which as shown is circular in form andcomprises a slightly pitched upper surface or top generally designatedlil supported on a dependent side wall 12 formed by a ring (see FIG. 3)of rigid polyurethane foam. The foam ring 12 provides adequate buoyancewhen the raft is in the water to support swimmers with a total weight inthe neighborhood of 2500 lbs. if need be, and marginally defines aclosed space or chamber 13 between the water 1'4 and the top or supportsurface 1.1.

As FIGS. 1 and 2 particularly indicate, the surface of the raft top 11is configured to pie-shaped sections .'15 separated by narrow smoothsurfaced portions 16 which at their radially inner ends merge into asmooth surfaced circular central portion 17. The pie-shaped sections areprovided with a tread surface, as shown at I15, and it is to beunderstood that this tread surface 15' is provided in exactly the samemanner on each pie-shaped segment 15. 'Further it will be noted that thetread surface 15 extends to a rounded peripheral edge portion 18' whichjoins the top 11 with the outer peripheral surface of the ring 12. Thetread surface consists of parallel grooves x and y with mounds m betweenthem having fiatted off central portions z.

The construction of the raft perhaps can best be understood from aninspection of FIGS. 4 and 5. It should be understood that the raft isformed in a female mold, and the surface configuration of the mold formsthe tread portions 15 and the portions 116, 17 and 18. In forming theraft a polyester gel coat 19 (see FIG. 5) in the nature of .G12-.020 inthickness is first sprayed into the mold cavity and forms the outerexterior surface of the top 1^1 and side 12. Then a fibre glass andresin layer 20` approximately 1/s in thickness is sprayed into thecavity and forms an immediately underneath layer. The resin may be asuitable commercial polyester with a setting catalyst. The next stepinvolves inserting pie-shaped plywood pieces about 3A in thickness inthe mold to form rigid core sections. As FIG, 4 indicates the pie-shapedplywood members 21 are disposed in slightly spaced apart relationship asat 22, and do not fully meet at their radially inner ends. The segmentmembers 21 may extend radially inwardly about the same distance as dothe portions 15 shown in FIGS. 1 and 2 and, in fact, may be the sameshape as the portions -15 shown in FIG. 2.

The inner ends of the plywood segments 21 are joined together by aplywood block 22 about 3%1 in thickness which is simply laid over them.Then finally a finish fibre glass resin coating 22a about 1/16 inthickness is sprayed over the interior of the raft and when set anchorsthe block 22 to the segments 21 to provide a unitary core structure. Thespaces between segments 21 do not completely fill with resin and grooves2211 remain. Because the pie-shaped plywood sections 21 do not extendall the way to the center of the raft a space 23 is left between them(see FIG. 5), and this space accommodates a nut 24 which secures an eyebolt `25 in position. The eye bolt 25 forms a ring to which an anchorchain may be secured in any suitable manner.

The space 23 also provides a passage communicatmg with an opening 26extending through coatings 19, 20 and 22a and block 22. A normallyclosed conventional, depressible stem, tire valve 27 selectivelycommunicates the air chamber or space 13 with the exterior atmosphere.The valve may be a conventional Shrader valve of the type used onvehicle tires or could be any other suitable valve. The opening 26 ispreferably of a size to snugly receive the valve 27 which preferably isslightly recessed in the opening 26 so that the accessible, depressiblestem thereof lies slightly below the surface 17 of the raft.

The plywood segments 21 are slightly spaced apart as at 22 because it ishighly desirable to provide a crown or slope to the supper surface 11 ofthe raft to permlt water to drain off. It would not be possible toprovide such a crown with a circular core.

Once the raft is formed and placed in the water as shown in FIG. 3, itmay be vacuum locked in position in a manner in which will now bedescribed. The top of the raft is loaded as, for example, by placingsand bags on it to cause it to sink lower into the water, and this hasthe effect of compressing the air in chamber 13 so that it now assumes apressure greater than atmospheric pressure. If the stem of the valve 27is now depressed by a person sitting on the raft, air may be evacuatedfrom the chamber 13 to the desired degree. rlfhen, when the sand bags orother weights are removed, the raft raises in accordance with the amountof air which has been removed so that the air in chamber 13 is now belowatmospheric pressure and the raft accordingly is vacuum locked inposition. The height of the raft in the water may be varied with theamount of air which is removed in this way, and by vacuum locking theraft to the water a great stability is provided which permits divingfrom the raft without displacing it. The stability further permitsboarding of the raft as with a ladder anchored to the side thereofwithout any chance of tipping the raft. The raft is described in theappended claims.

I claim:

1. A buoyant body oating in water comprising: a top; means forming abuoyancy providing perimetral section below the top and immersed in thewater; said body including a wall bounding a closed inner air chamberbetween the water and top; and normally closed opening means normallyclosed to prevent air flow between said chamber and the exterioratmosphere, but openable to open the chamber to the exterior atmosphere;the pressure in said chamber being substantially less than atmospheric,when the body is ilioating normally upright in the water without load,to vacuum lock the body to the water.

2. The combination defined in claim 1 in which said top has a non-skidtread surface thereon and the tread surface comprises a surface havingcross-hatched grooves defining squares with raised flatted-oi mounds.

3. A floating body comprising: a downwardly and outwardly sloping top;and a side wall including a generally perimetral skirt portion extendingdownwardly a substantial distance from the underside thereof to form thebottom of the side wall; said skirt in cross-section constituting ablock of coated plastic foam having suicient height and width to providefor -tloating the raft in unloaded condition with the top raised asubstantial distance out of the water and the skirt substantiallyimmersed in the water, said perimetral skirt being of a width to dene agenerally centrally symmetric-compartment of substantial size inward ofsaid skirt under said top, and open at its bottom; said top having aconfigured non-skid tread surface, and outwardly and downwardly slopingnarrow drain channels, depressed relative to the top of the treadsurface, extending from a central portion of the top of the body to theperimetral edges thereof and separating the tread surface into sections.

4. The combination defined in claim 3 in which the tread surfacecomprises a surface having cross-hatched grooves defining squares withraised flatted ot mounds.

5. The combination of claim 3 wherein said foam comprises a rigidplastic foam ring joined iush with the periphery of said top; said treadsurface comprises grooves cross-hatched in the surface with flatted offmounds between said grooves; and said top comprises relatively closelyspaced, segment shaped plywood core sections covered on top by ahardened bre glass and resin composition.

6. The combination defined in claim 5 in which the upper surface of saidcomposition is covered by a nish plastic coating; said core sections arecentrally joined by a plywood piece to provide a unitary structure; theunderside of said core sections and piece are coated with a hardenedfibre glass and resin composition to bind the piece and core sectionstogether; and said composition binds said foam ring to said top.

7. The combination defined in claim 6 in which the inner ends of saidcore sections do not meet and a central space remains between them; avalve passage communicates said space with the air chamber formed undersaid top .by the ring and the exterior of said top; a normally closedvalve in said passage; an anchor ring mounts on said plywood piece, andanchor means in said central space locks it in position.

8. A oating body comprising: a top; and a side wall including agenerally perimetral skirt portion extending downwardly a substantialdistance from the underside thereof to form the bottom of the side wall;said skirt in cross-section constituting a block of coated plastic foamhaving sufficient height and width to provide for oating the raft inunloaded condition with the top raised a substantial distance out of thewater and the skirt substantially immersed in the water; said perimetralskirt being of a width to define generally centrally symmetriccompartment means of substantial size inward of said skirt under saidtop and open at the bottom; said compartment constituting a closed airchamber between the water and top when the raft is in :the water; andnormally closed opening means in said top, normally preventing air flowin either direction between said chamber and atmosphere, but openable tocommunicate said chamber with the exterior atmosphere.

References Cited UNITED STATES PATENTS 2,287,518 6'/ 1942 Flynn 9-112,421,171 5/ 1947 Trautvetter et al 52-181 2,858,790 11/1958 Russell,Jr. 9-11 3,048,859 l8/1962 Maillot 9-11 3,090,339 5/1963 Carr 9--113,172,343 3/1965 Jacobs 52-177 3,179,076 4/ 1965 Sheiiield 9 1 13,344,764 l`0/ 1967 Ziermann 9--11 3,035,286 5/ 1962 Brill 9-11 MILTONBUCHLER, Primary Examiner S. W. WEINRIEB, Assistant Examiner U.S. Cl.X.R. 4G-91; 272--1 B

